Understand the differences between Mean Absolute Error (MAE) and Root Mean Squared Error (RMSE), how to choose the right metric for your prediction task, and the impact of large errors on each.
regression / model evaluation / MAE / RMSE / error metrics / scikit-learn / machine learning
Read training and validation scores together, fit preprocessing inside a pipeline and keep a final test set out of model selection.
Machine Learning / Validation / Overfitting
Build a previous-season reference, evaluate it on later observations and distinguish calendar alignment from leakage and missing data.
Time Series / Forecasting / Baseline / Validation
Use chronological splits and fit preprocessing only on past data.
Python / Time series / Validation